How many layers cover the eye ball of humans ?

Options

A. 3
B. 6
C. 4
D. 2

Answer

**Step-by-Step Solution:**

1. **Understanding the Structure of the Eyeball**: The human eyeball is a nearly spherical structure that is covered by multiple layers.

2. **Identifying the Layers**: There are three distinct layers that cover the human eyeball:
- **Outer Layer (Sclera)**: This is the tough, white outer layer made of dense connective tissue. It provides protection and structure to the eyeball.
- **Middle Layer (Choroid)**: This layer contains many blood vessels and is responsible for supplying nutrients to the eye. It also has a bluish color.
- **Inner Layer (Retina)**: This is the innermost layer that contains photoreceptor cells (rods and cones) responsible for vision. It also includes bipolar cells and ganglion cells.

3. **Conclusion**: Since the eyeball is covered by three layers (sclera, choroid, and retina), the answer to the question is that there are **three layers** covering the human eyeball.

**Final Answer**: The human eyeball is covered by **three layers**.

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